[newlib-cygwin] dll_list: Track main executable and cygwin1.dll.
Corinna Vinschen
corinna@sourceware.org
Fri Feb 8 11:37:00 GMT 2019
https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=dac0b6826bef8c637866c60d15ffd8461b361f50
commit dac0b6826bef8c637866c60d15ffd8461b361f50
Author: Michael Haubenwallner <michael.haubenwallner@ssi-schaefer.com>
Date: Wed Dec 7 11:58:26 2016 +0100
dll_list: Track main executable and cygwin1.dll.
Even for the main executable and cygwin1.dll store the file name as full
NT path. Create the child process using the main executable's file name
converted from the full NT path stored before.
* dll_init.cc (dll_list::alloc): Search for DLL_SELF type entry
with module name like for DLL_LINK, use full NT path to search
for DLL_LOAD type only. For DLL_SELF type do not indicate
having a destructor to be called.
(dll_list::find): Ignore DLL_SELF type entries.
(dll_list::init): Ditto. Call track_self method.
(dll_list::track_self): New.
(dll_list::load_after_fork): Call track_self method.
* dll_init.h (enum dll_type): Add DLL_SELF, for the main
executable and cygwin1.dll.
(struct dll_list): Declare private method track_self. Declare
member variable main_executable.
* fork.cc (frok::parent): Use ntname from dlls.main_executable
to create child process, converted to short path using
dll_list::buffered_shortname.
Diff:
---
winsup/cygwin/dll_init.cc | 26 ++++++++++++++++++++------
winsup/cygwin/dll_init.h | 4 ++++
winsup/cygwin/fork.cc | 15 ++++++++++++---
3 files changed, 36 insertions(+), 9 deletions(-)
diff --git a/winsup/cygwin/dll_init.cc b/winsup/cygwin/dll_init.cc
index f94c669..2204533 100644
--- a/winsup/cygwin/dll_init.cc
+++ b/winsup/cygwin/dll_init.cc
@@ -306,8 +306,9 @@ dll_list::alloc (HINSTANCE h, per_process *p, dll_type type)
guard (true);
/* Already loaded? For linked DLLs, only compare the basenames. Linked
DLLs are loaded using just the basename and the default DLL search path.
- The Windows loader picks up the first one it finds. */
- dll *d = (type == DLL_LINK) ? dlls.find_by_modname (modname) : dlls[ntname];
+ The Windows loader picks up the first one it finds.
+ This also applies to cygwin1.dll and the main-executable (DLL_SELF). */
+ dll *d = (type != DLL_LOAD) ? dlls.find_by_modname (modname) : dlls[ntname];
if (d)
{
/* We only get here in the forkee. */
@@ -339,7 +340,8 @@ dll_list::alloc (HINSTANCE h, per_process *p, dll_type type)
d->modname = d->ntname + (modname - ntname);
d->handle = h;
d->count = 0; /* Reference counting performed in dlopen/dlclose. */
- d->has_dtors = true;
+ /* DLL_SELF dtors (main-executable, cygwin1.dll) are run elsewhere */
+ d->has_dtors = type != DLL_SELF;
d->p = p;
d->ndeps = 0;
d->deps = NULL;
@@ -526,7 +528,7 @@ dll_list::find (void *retaddr)
dll *d = &start;
while ((d = d->next))
- if (d->handle == h)
+ if (d->type != DLL_SELF && d->handle == h)
break;
return d;
}
@@ -566,11 +568,22 @@ dll_list::detach (void *retaddr)
void
dll_list::init ()
{
+ track_self ();
+
/* Walk the dll chain, initializing each dll */
dll *d = &start;
dll_global_dtors_recorded = d->next != NULL;
while ((d = d->next))
- d->init ();
+ if (d->type != DLL_SELF) /* linked and early loaded dlls */
+ d->init ();
+}
+
+void
+dll_list::track_self ()
+{
+ /* for cygwin1.dll and main-executable: maintain hardlinks only */
+ alloc (cygwin_hmodule, user_data, DLL_SELF);
+ main_executable = alloc (GetModuleHandle (NULL), user_data, DLL_SELF);
}
#define A64K (64 * 1024)
@@ -637,7 +650,7 @@ dll_list::reserve_space ()
/* Reload DLLs after a fork. Iterates over the list of dynamically loaded
DLLs and attempts to load them in the same place as they were loaded in the
- parent. */
+ parent. Updates main-executable and cygwin1.dll tracking. */
void
dll_list::load_after_fork (HANDLE parent)
{
@@ -647,6 +660,7 @@ dll_list::load_after_fork (HANDLE parent)
in_load_after_fork = true;
if (reload_on_fork)
load_after_fork_impl (parent, dlls.istart (DLL_LOAD), 0);
+ track_self ();
in_load_after_fork = false;
}
diff --git a/winsup/cygwin/dll_init.h b/winsup/cygwin/dll_init.h
index 4897c42..369fc54 100644
--- a/winsup/cygwin/dll_init.h
+++ b/winsup/cygwin/dll_init.h
@@ -40,6 +40,7 @@ struct per_module
typedef enum
{
DLL_NONE,
+ DLL_SELF, /* main-program.exe, cygwin1.dll */
DLL_LINK,
DLL_LOAD,
DLL_ANY
@@ -75,6 +76,8 @@ struct dll
class dll_list
{
+ void track_self ();
+
dll *end;
dll *hold;
dll_type hold_type;
@@ -94,6 +97,7 @@ public:
return nt_max_path_buffer;
}
+ dll *main_executable;
dll start;
int loaded_dlls;
int reload_on_fork;
diff --git a/winsup/cygwin/fork.cc b/winsup/cygwin/fork.cc
index c78e5cf..adcd1d7 100644
--- a/winsup/cygwin/fork.cc
+++ b/winsup/cygwin/fork.cc
@@ -175,7 +175,7 @@ frok::child (volatile char * volatile here)
if (fixup_shms_after_fork ())
api_fatal ("recreate_shm areas after fork failed");
- /* load dynamic dlls, if any */
+ /* load dynamic dlls, if any, re-track main-executable and cygwin1.dll */
dlls.load_after_fork (hParent);
cygheap->fdtab.fixup_after_fork (hParent);
@@ -310,11 +310,20 @@ frok::parent (volatile char * volatile stack_here)
while (1)
{
+ PCWCHAR forking_progname = NULL;
+ if (dlls.main_executable)
+ forking_progname = dll_list::buffered_shortname
+ (dlls.main_executable->ntname);
+ if (!forking_progname || !*forking_progname)
+ forking_progname = myself->progname;
+
syscall_printf ("CreateProcessW (%W, %W, 0, 0, 1, %y, 0, 0, %p, %p)",
- myself->progname, myself->progname, c_flags, &si, &pi);
+ forking_progname, myself->progname, c_flags, &si, &pi);
hchild = NULL;
- rc = CreateProcessW (myself->progname, /* image to run */
+ /* cygwin1.dll may reuse the forking_progname buffer, even
+ in case of failure: don't reuse forking_progname later */
+ rc = CreateProcessW (forking_progname, /* image to run */
GetCommandLineW (), /* Take same space for command
line as in parent to make
sure child stack is allocated
More information about the Cygwin-cvs
mailing list